Front portion of an aircraft



FIG. 1 is a front elevation view of a front portion of an aircraft according to my design;

FIG. 2 is a right side elevation view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof.

No rear elevation view is included as no features of the claimed design are visible therein. 

The ornamental design for a front portion of an aircraft, as shown and described. 